I n t h I s c h a p t e r y o u w I l L

comparative advantage
when describing the oppor-
tunity cost of two producers. The producer who has the smaller opportunity cost
a b s o l u t e a d v a n t a g e
the comparison among producers of a
good according to their productivity
o p p o r t u n i t y c o s t
whatever must be given up to obtain
some item
c o m p a r a t i v e a d v a n t a g e
the comparison among producers
of a good according to their
opportunity cost

---

5 4
PA R T O N E
I N T R O D U C T I O N
of producing a good—that is, who has to give up less of other goods to produce
it—is said to have a comparative advantage in producing that good. In our exam-
ple, the farmer has a lower opportunity cost of producing potatoes than the
rancher (1/2 pound versus 8 pounds of meat). The rancher has a lower opportu-
nity cost of producing meat than the farmer (1/8 pound versus 2 pounds of pota-
toes). Thus, the farmer has a comparative advantage in growing potatoes, and the
rancher has a comparative advantage in producing meat.
Notice that it would be impossible for the same person to have a comparative
advantage in both goods. Because the opportunity cost of one good is the inverse
of the opportunity cost of the other, if a person’s opportunity cost of one good is
relatively high, his opportunity cost of the other good must be relatively low. Com-
parative advantage reflects the relative opportunity cost. Unless two people have
exactly the same opportunity cost, one person will have a comparative advantage
in one good, and the other person will have a comparative advantage in the other
good.
C O M PA R AT I V E A D VA N TA G E A N D T R A D E
Differences in opportunity cost and comparative advantage create the gains from
trade. When each person specializes in producing the good for which he or she has
a comparative advantage, total production in the economy rises, and this increase
in the size of the economic pie can be used to make everyone better off. In other
words, as long as two people have different opportunity costs, each can benefit
from trade by obtaining a good at a price lower than his or her opportunity cost of
that good.
Consider the proposed deal from the viewpoint of the farmer. The farmer gets
3 pounds of meat in exchange for 1 pound of potatoes. In other words, the farmer
buys each pound of meat for a price of 1/3 pound of potatoes. This price of meat
is lower than his opportunity cost for 1 pound of meat, which is 2 pounds of pota-
toes. Thus, the farmer benefits from the deal because he gets to buy meat at a good
price.
Now consider the deal from the rancher’s viewpoint. The rancher buys 1
pound of potatoes for a price of 3 pounds of meat. This price of potatoes is lower
than her opportunity cost of 1 pound of potatoes, which is 8 pounds of meat. Thus,
the rancher benefits because she gets to buy potatoes at a good price.
These benefits arise because each person concentrates on the activity for which
he or she has the lower opportunity cost: The farmer spends more time growing
potatoes, and the rancher spends more time producing meat. As a result, the total
production of potatoes and the total production of meat both rise, and the farmer
Ta b l e 3 - 3
T
HE
O
PPORTUNITY
C
OST OF
M
EAT AND
P
OTATOES